BACKGROUND: Although neferine exhibits obvious therapeutic effects against hypertension, its effects on cardiac protection remain unknown. PURPOSE: This study aimed to investigate its potential cardioprotective effects and associated mechanisms. METHODS: Spontaneously hypertensive rats (SHRs) were randomly divided into four groups, namely SHR, SHR + Neferine-L (2.5 mg/kg/day), SHR + Neferine-M (5 mg/kg/day), and SHR + Neferine-H (10 mg/kg/day). Wistar Kyoto rats were used as control. Various concentrations of neferine or double distilled water were then administered intragastrically for 10 weeks. Thereafter, cardiac function, pathological changes, cell apoptosis, and reactive oxygen species (ROS) accumulation, as well as their underlying mechanisms, were evaluated in SHRs and/or hypoxia-induced H9c2 cells. RESULT: Neferine treatment significantly mitigated the decrease in left ventricular ejection fraction and fractional shortening and increase in left ventricular mass, end-systolic volume, and cardiac injury in SHRs. In SHR cardiac tissues, neferine treatment reversed 154 upregulated and 108 and downregulated transcripts. Pathway enrichment analysis found that multiple pathways were commonly enriched, including the apoptosis, PI3K-Akt, MAPK, and HIF-1 pathways. Consistently, neferine treatment significantly mitigated cardiomyocyte apoptosis, restored mitochondrial membrane depolarization, and reduced ROS accumulation. Mechanistically, neferine treatment significantly decreased the phosphorylation of ERK, p38 MAPK, and JNK
the Bax/Bcl-2 ratio
and the expression of HIF-1α, NADPH oxidase 4, and cleaved caspases-3 and -9 but increased the phosphorylation of PI3K and Akt and the expression of CD31. CONCLUSION: Neferine treatment effectively mitigated hypertensive cardiomyocyte apoptosis and attenuated the abnormal activation of multiple signaling pathways, including the PI3K/Akt, MAPK, and HIF-1 pathways.